000002738 001__ 2738 000002738 005__ 20180208225122.0 000002738 0247_ $$2DOI$$a10.1088/0953-8984/20/14/142202 000002738 0247_ $$2WOS$$aWOS:000254175100002 000002738 037__ $$aPreJuSER-2738 000002738 041__ $$aeng 000002738 082__ $$a530 000002738 084__ $$2WoS$$aPhysics, Condensed Matter 000002738 1001_ $$0P:(DE-HGF)0$$aZiebinska, A.$$b0 000002738 245__ $$aBirefringence above T_c in single crystals of barium titanate 000002738 260__ $$aBristol$$bIOP Publ.$$c2008 000002738 300__ $$a142202 000002738 3367_ $$0PUB:(DE-HGF)16$$2PUB:(DE-HGF)$$aJournal Article 000002738 3367_ $$2DataCite$$aOutput Types/Journal article 000002738 3367_ $$00$$2EndNote$$aJournal Article 000002738 3367_ $$2BibTeX$$aARTICLE 000002738 3367_ $$2ORCID$$aJOURNAL_ARTICLE 000002738 3367_ $$2DRIVER$$aarticle 000002738 440_0 $$03703$$aJournal of Physics: Condensed Matter$$v20$$x0953-8984 000002738 500__ $$aRecord converted from VDB: 12.11.2012 000002738 520__ $$aThe temperature dependence of the birefringence above T-c in high quality BaTiO3 single crystals has been measured with very high accuracy. On the basis of literature data, the behaviour of the anomalous birefringence can be explained by the existence of polar clusters (microregions/nanoregions) connected with correlated jumps between the off-centre positions of Ti ions inside the oxygen octahedra. The underlying origin of the polar clusters is an intrinsic effect connected with the interdependence of the structural and polar soft modes (Bussmann-Holder et al 2007 Phys. Rev. Lett. 99 167603). These clusters locally break the intrinsic cubic symmetry and the phase above T-c becomes birefringent. A birefringence Delta n of the order of 10(-5) has been found up to about 30 degrees above T-c. In this temperature range T-c < T < T-c + 30 K, the function Delta n(T) exhibits a thermal hysteresis: the values of Delta n were higher on heating than on cooling. A characteristic feature is the existence of a local Delta n(T) maximum at a temperature close to T-c on the high temperature side that appears due to a specific cluster-cluster interaction. Since the values of Delta n(T) runs were not dependent on the crystal thickness, one can conclude that in this limited temperature range above T-c the birefringence is an inherent feature of the crystal. 000002738 536__ $$0G:(DE-Juel1)FUEK412$$2G:(DE-HGF)$$aGrundlagen für zukünftige Informationstechnologien$$cP42$$x0 000002738 588__ $$aDataset connected to Web of Science 000002738 650_7 $$2WoSType$$aJ 000002738 7001_ $$0P:(DE-HGF)0$$aRytz, D.$$b1 000002738 7001_ $$0P:(DE-Juel1)VDB2799$$aSzot, K.$$b2$$uFZJ 000002738 773__ $$0PERI:(DE-600)1472968-4$$a10.1088/0953-8984/20/14/142202$$gVol. 20, p. 142202$$p142202$$q20<142202$$tJournal of physics / Condensed matter$$v20$$x0953-8984$$y2008 000002738 8567_ $$uhttp://dx.doi.org/10.1088/0953-8984/20/14/142202 000002738 909CO $$ooai:juser.fz-juelich.de:2738$$pVDB 000002738 9131_ $$0G:(DE-Juel1)FUEK412$$bSchlüsseltechnologien$$kP42$$lGrundlagen für zukünftige Informationstechnologien (FIT)$$vGrundlagen für zukünftige Informationstechnologien$$x0 000002738 9141_ $$y2008 000002738 915__ $$0StatID:(DE-HGF)0010$$aJCR/ISI refereed 000002738 9201_ $$0I:(DE-Juel1)VDB786$$d31.12.2010$$gIFF$$kIFF-6$$lElektronische Materialien$$x0 000002738 9201_ $$0I:(DE-82)080009_20140620$$gJARA$$kJARA-FIT$$lJülich-Aachen Research Alliance - Fundamentals of Future Information Technology$$x1 000002738 970__ $$aVDB:(DE-Juel1)107862 000002738 980__ $$aVDB 000002738 980__ $$aConvertedRecord 000002738 980__ $$ajournal 000002738 980__ $$aI:(DE-Juel1)PGI-7-20110106 000002738 980__ $$aI:(DE-82)080009_20140620 000002738 980__ $$aUNRESTRICTED 000002738 981__ $$aI:(DE-Juel1)PGI-7-20110106 000002738 981__ $$aI:(DE-Juel1)VDB881